A massive manhunt is underway in search of the two suspects in the Charlie Hebdo attack.Reuters

Anti-terror police are searching dense woodland as an international manhunt continues for two gunmen, suspected of killing 12 people in the Charlie Hebdo attack.

Police earlier confirmed that two men, fitting the descriptions of brothers Said and Cherif Kouachi, stole fuel and food from a petrol station near Villers-Cotterets, in the northern Aisne region, 43 miles (70km) from Paris, this morning.

Heavily-armed police have been going house to house, searching the village of Crepy-en-Valois, 10 miles (16km) from the petrol station and scrutinising each resident.

The search is now being extended to a stretch of countryside from Soissons, through Abbaye de Longpont, up to Villers-Cotteret.

The forest near Longpont, is said to be bigger than Paris, measuring some 13,000 hectares, or 50 square miles.

It has been reported that the men were holed up in a house in the local area, however Crepy-en-Valois' mayor Bruno Fortier said he could not confirm this.

"It's an incessant waltz of police cars and trucks," he told Reuters.

Earlier the suspects were spotted travelling on the N2 road in the direction of Paris in a Renault Clio which had weapons on its back seat and its number plates covered.

AFP said the pair had Kalashnikovs and what appeared to be a rocket-launcher.

RAID, the French anti-terrorist unit, and GIGN, a paramilitary special operations unit, have been deployed in the region.

Officials have said the French nationals are linked to a Yemeni terror network.

On Wednesday night heavily armoured police raided an apartment in the city of Reims in the search for the killers. Seven people were detained overnight.

Another suspect handed himself in to police after he was named on social media as 18-year-old Hamyd Mourad. He was alter identified as the brother-in-law of the suspects.

French investigators found a dozen Molotov cocktails and two jihadist flags in the black Citroen getaway car abandoned shortly after Wednesday's massacre.